A wireless access point can function as an access point and it can also be used as a repeater....
hub
The function of a wireless access point is to allow wireless devices such as projectors, laptops and PDAs to access a local area network. Wireless access points mainly act as switches to spread...
switch hub
wireless access point (a wireless networking item)
That depends on what you are attempting to do. If you are trying to access the internet, then no, a wireless router is not needed.